1. Field
One embodiment of the invention relates to an image processing apparatus and an image processing method.
2. Description of the Related Art
There have been image processing apparatuses that are know as performing conversion (hereinafter, “scaling”) on an input image signal to convert the number of pixels thereof to the number compatible with a display device. More specifically, such an image processing apparatus performs scaling on an image with standard definition (SD) resolution (720×480 pixels) to convert the resolution to, for example, 1440×1080 pixels (see, for example, Japanese Patent Application Publication (KOKAI) No. 2006-287506). Besides, there have been image processing apparatuses that are know as performing sharpening on an image of an input image signal to increase the resolution of the image (see, for example, Japanese Patent Application Publication (KOKAI) No. 2007-310837).
However, if sharpening is performed on an input image after scaling is performed thereon, in the case of a graphics image that has a sharp peak at a predetermined luminance gray level differently from a natural image in which the luminance gray level gradually changes, the noise is emphasized, resulting in significant degradation of the image. This is because sharpening is a process to be applied to a natural image. Therefore, if sharpening is performed on a graphics image to achieve an effect equivalent to that on a natural image, noise is likely to occur in pixels increased to enhance the resolution of the image.